k8s.github.io

Test the cluster

Here we will test the cluster by creating a workload with a node port service and get the results using curl

Do the following on controlplane

1. Deploy and expose an nginx pod

    kubectl create deployment nginx --image nginx:alpine
    kubectl expose deploy nginx --type=NodePort --port 80
   
    PORT_NUMBER=$(kubectl get service -l app=nginx -o jsonpath="{.items[0].spec.ports[0].nodePort}")
    echo -e "\n\nService exposed on NodePort $PORT_NUMBER"
   

1. Hit the new service

   curl http://node01:$PORT_NUMBER
   curl http://node02:$PORT_NUMBER
   

   If you get this error:

   curl: (7) Failed to connect to node01 port 30659 after 0 ms: Connection refused
   

   Wait a few seconds and try again. Both should return the nginx welcome message as HTML text.

Congratulations! You now have a working kubeadm cluster.

Viewing service with a browser

VirtualBox or Apple Silicon

If you installed the cluster with bridge networking (the default), then you can view NodePort services with your browser.

Run the following command on controlplane to get browser address, then copy the output to your browser:

echo "http://$(dig +short node01):$PORT_NUMBER"

AWS

1. Refer to the outputs of the terraform run and get the IP address for either node01 or node02. If you did not note these down, you can find the IP addresses from the EC2 console by looking in the Public IPv4 ... column (scroll right if this column is not in view).

2. Form a URL using the IP address (it will be different for you) and the NodePort number output from step 1 above, e.g.

    http://54.167.161.210:32182
   

3. Paste URL to your browser

You may also copy the KUBECONFIG to student-node thus allowing you to run kubectl commands from there:

1. Return to student-node.

2. Run the following:

    mkdir ~/.kube
    scp controlplane:~/.kube/config ~/.kube/config
    kubectl get pods -n kube-system
   

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